This invention relates to shelf assemblies, and more particularly to an assembly for connecting a shelf to an upright post or posts, or to another shelf.
Heretofore, in shelf assemblies, and more particularly in "knock-down" shelf assemblies, various connector devices have been devised for connecting the corners of the shelves to corresponding upright posts. One of the most common, and perhaps most prevalent, connector assemblies includes various types of bracket and bolt assemblies for bolting the corners of the shelves to the posts. However, in order to adjust the height of the shelf and post, the bolts must be loosened, tightened, removed, and re-inserted, all of which operations require the use of a tool, such as a screw driver, wrench or pliers, or a combination of such tools. Such operations require considerable time, since in a shelf assembly incorporating a plurality of shelves, one bolt for each of the four corners of the multitude of shelves must be manipulated. In such operations, the threads of bolts become stripped, bolts become lost, and in some corner connections, the bolt shanks bear the entire weight of a loaded shelf, thereby exerting substantial sheer stresses upon the bolts.
The following U.S. and foreign patents disclose other types of connectors for connecting the corners of shelves to upright members:
U.S. Pat. No. 3,138,123, Maslow, June 23, 1964 PA1 U.S. Pat. No. 3,208,408, Maslow, Sept. 28, 1965 PA1 U.S. Pat. No. 3,208,777, Maslow, Sept. 28, 1965 PA1 U.S. Pat. No. 3,225,720, Maslow, Dec. 28, 1965 PA1 U.S. Pat. No. 3,245,365, Doherty, Apr. 12, 1966 PA1 U.S. Pat. No. 3,316,864, Maslow, May 2, 1967 PA1 U.S. Pat. No. 3,344,756, Kelson, Oct. 3, 1967 PA1 U.S. Pat. No. 3,424,111, Maslow, Jan. 28, 1969 PA1 U.S. Pat. No. 3,523,508, Maslow, Aug. 11, 1970 PA1 U.S. Pat. No. 3,675,598, Kesilman et al, July 11, 1972 PA1 U.S. Pat. No. 3,757,705, Maslow, Sept. 11, 1973 PA1 U.S. Pat. No. 3,858,530, Jaffee et al, Jan. 7, 1975 (Bolt-type) PA1 U.S. Pat. No. 3,874,511, Maslow, Apr. 1, 1975 PA1 U.S. Pat. No. 3,927,769, Maslow, Dec. 23, 1975 PA1 U.S. Pat. No. 855,715, France, Feb. 19, 1940
All of the recent Maslow patents commencing with the Maslow U.S. Pat. No. 3,424,111, disclose tapered corner collars fixed to, or forming a part of, the shelf and adapted to cooperate with a pair of truncated-conical sleeves disposed about corresponding grooved upright posts.
The Kesilman U.S. Pat. No. 3,675,598, discloses cooperating tapered sleeves and corner collars for shelves in which the upright post is not grooved, and therefore requires a set screw for securing the conical sleeves to the post.
There is another corner connector for shelves and upright posts commercially available and produced by Gillis & Associates, Inc., of Prospect Heights, Ill., in their "Cari-All" shelf assemblies. The "Cari-All" corner connector includes a square U-shaped clip adapted to fit around three corresponding sides of an upright post. However, the corners of the clip are notched to engage corresponding recesses in the corners of the square tube. The clip is provided with hook members projecting from both sides of the clip to receive horizontal rods of the corresponding shelf. Thus, this "Cari-All" Clip is only adaptable for connecting wire-type shelves.